There are many different kinds of hamsters, but the five most common are Syrians, Dwarf Campbell Russians, Dwarf Winter White Russians, Roborovski Dwarfs, and Chinese. Each breed has its own distinctive characteristics that distinguish it from the other breeds.

Syrian Hamsters (Mesocricetus auratus)
Syrian hamsters, also known as Goldens or Teddy Bear hamsters, are the most popular hamsters kept as pets. They are very easy to handle and make wonderful pets for children. They are not social with other hamsters however, and should be kept alone after 10 weeks of age. If caged together, Syrian hamsters can actually fight until they kill each other. Syrian hamsters are nocturnal, and are rarely active during the day.

Syrian hamsters come in a variety of colors, and they are one of the largest hamsters at a length of 4" - 7" when full grown, depending on the sex. Females can grow larger than the males, which reach only about 6" long. They have a very short tail, large cheek pouches, and small eyes. The average life span of a Syrian hamster is approximately 2 to 2-1/2 years, though they have been known to live as long as 4 years.

Dwarf Campbell Russian Hamsters (Phodopus campbelli)
Dwarf Campbell Russian hamsters are more social than Syrian hamsters, and they can be kept in same sex pairs or groups of their breed as long as they are introduced at a young age. They aren't quite as responsive to handling as Syrians and may nip if they feel nervous or threatened. They still make good pets; they just require supervision of both child and pet during interactions. Though they are nocturnal, they are often awake for short periods during the day.

Dwarf Campbell Russians are very small, reaching a maximum size of only 4" as adults. The natural coat color is grayish brown fur on the back with a darker strip of color down the spine, a creamier color on the sides, and a white stomach. Dwarf Campbell Russians can be found in a variety of colors however, due to selective breeding. The average life span of a Dwarf Campbell Russian is about 2 years.

Dwarf Winter White Russian Hamsters (Phodopus sungorus)
Dwarf Winter White Russian hamsters are similar in behavior to Dwarf Campbell Russians in that they are active during the day and can be kept in same sex pairs or groups. However, they do not have the reputation for biting when nervous, and they are generally very sweet and personable. They are very small and quick though, so they can be a challenge for young children to handle safely.

Dwarf Winter White Russians come in three colors: Sapphire, Pearl, and a combination of the two called Sapphire-Pearl. Pearl is a white pattern where white hairs are sprinkled throughout the coat, and Sapphire is a purple-gray color. Sapphire Winter White Russians have a gray undercoat, a thick gray stripe along their spines, and an ivory colored stomach.

Dwarf Winter White Russians are very small and compact, measuring only 3-1/2" to 4" as full grown adults. Because they are so tiny, an aquarium is generally a safer housing choice than a wire cage. The average life span of a Dwarf Winter White Russian hamster is about 2 years.

Roborovski Dwarf Hamsters (Phodopus roborovski)
Roborovski Dwarfs are another social breed of hamster, and they do well in small same sex pairs or groups if they are introduced at a young age. They are sweet hamsters that do not usually nip. Though they have good temperaments, they are generally better for observation than for handling because of their size and agility. They should only be handled where they will be easy to catch if they jump down from your hands. They are nocturnal.

Roborovski hamsters are sandy brown with a white stomach, white marks over their eyes, and occasionally a white face. They are the smallest of the most popular hamster breeds, reaching an adult size of only 1-1/2" to 2". The average life span of a Roborovski is longer than any of the other common hamster breeds at 3 to 3-1/2 years.

Chinese Hamsters (Cricetulus griseus)
Chinese hamsters, also known as Striped hamsters or Chinese Striped hamsters, are not generally social hamsters, but there have been some owners who have been able to successfully house them together. However, it's best to be safe and house them individually. Though they can be aggressive towards each other, they are good-natured towards people and slightly timid, and they rarely bite. They are active during short periods throughout the day, but their most active period is at night.

Chinese hamsters are often mistakenly referred to as dwarf hamsters. Though at about 4" full grown they are similar in size to other dwarf hamsters, they are actually not true dwarfs. Chinese hamsters have a body type that is similar to a rat or mouse - long and slender. There are two colors of Chinese hamsters. The first, and most common, is an agouti coat with a dark brown back, a black line of fur along the spine, and an ivory colored stomach. The other color is called a "dominant spot," and it is a white coat with spots of color. The average life span of Chinese hamsters is about 1-1/2 to 2 years.